ZeroAvia has started an internal investigation into the accident in which its Piper M Series research and development aircraft was damaged in an off-airport landing during flight testing on April 29. The company said it will cooperate with the independent investigation conducted by the UK’s Air Accident Investigation Branch (AAIB).
The incident is expected to delay the conclusion of the HyFlyer 1 demonstration program, which was due to be completed over the next few weeks with longer-range flights of up to 250 miles. However, ZeroAvia said that it does not expect any negative impact to its HyFlyer 2 program's objective of bringing a 10- to 20-seat hydrogen-powered aircraft into commercial service by 2023 and a 50-seat airliner by 2026. The company believes its technology could support a 100-seat aircraft by 2030.
In a statement issued on May 1, ZeroAvia provided more details about the incident, which happened near the Cranfield airport in the UK, where it has been conducting flight testing since September 2020. It said that the Piper landed in a field just outside the airport perimeter during a routine pattern test flight (logged as ZeroAvia Test 86 and the 6th flight in the current testing segment).
“The aircraft landed normally on its wheels in a flat grass field and almost came to a stop but was damaged as it caught the left main gear and wing in the uneven terrain at the end of the field at low speed,” said the company statement. Neither of the two pilots on board was injured and the local fire service attended the scene of the landing, which happened just before 3:30 p.m. local time.
“The facts as they stand now are as follows,” continued the statement. “The flight conformed to the approved test route over the airport; the structural integrity of ZeroAvia systems was maintained throughout the incident sequence and there were no unintended hydrogen or electrical releases and no fire; after the landing, the crew were able to safeguard the battery and safely release hydrogen from the onboard tanks, following ZeroAvia safety protocol; no fluid leaks were observed at the time, and full data logs were preserved and will be used in our investigation.”
According to ZeroAvia, the propulsion system for the testbed aircraft consists of fuel cells and a battery from which power is transferred to an electric motor that drives the propeller.
The California-based company said that its internal investigation will be led by its head of airworthiness, Dominic Cheater, who was formerly chief of the office of airworthiness with helicopter operator Babcock. It claimed that the investigation team is independent of the HyFlyer 1 program's design and operations team and said that it will collaborate fully with the AAIB, which has yet to issue a statement on the incident.
The ZeroAvia investigation team also includes the following members: board director and former airline CEO Christine Ourmieres-Widener, who is a governor with the International Air Transport Association; global policy lead Richard King, a certified pilot who has held senior positions with the UK Ministry of Defence and Royal Navy; propulsion chief technology officer Yousef Abdelli, who was formerly chief engineer with aerospace manufacturer Liebherr and electric propulsion specialist MagniX; and flight test engineer James Yapp.
On March 31, ZeroAvia announced plans to develop a 50-seat airliner powered by hydrogen in a project that will be supported by $24.3 million in new capital raised by investors including British Airways. The company has been preparing to conduct a 70-mile flight between Cranfield and Kemble airfield in southern England. It has also intended to make a flight of around 250 miles later this year from the Orkney Islands to the Scottish mainland.